Method of shrouding blades.



are n' CHRISTIAN GILSON, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC @t MANUFACTURING COMPANY, A CORPORATION F PENNSYLVANIA.

METHOD OF SITIROUDING BLADES.

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Specification of Letters Patent.

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To all ywhom t mail concern:

Be it-knovvn that I, CHRISTIAN GILsoN, a citizen of the United States, and a resident of VVilliinsburg, in the county of Allegheny and State of Pennsylvania, have made a new and useful Invention in Methods of Shrouding Blades, of which the following is a specification. f

An object of this invention is to produce a new and improved method of shrouding blades, or is the production of blades having improved shrouding members formed thereon.

rIhis and other objects, Which will be made apparent throughout the furtherdescription of my invention, are attained by means of the method herein described and illustrated and by means ofthe blade constructed in accordance with that method.

In the drawings forming a part hereof, Figure 1 showsv in full lines a perspective view of a blade after it has been subjected to the first step in the ope-ration of forming shrouding members, in accordance with my invention, the dotted line construction showincr the inout blank.

Figs. 2 and 3 are perspective views of opposite sides of a blade and illustrate a blade which has been subjected to the second step of the method herein described as an embodiment of my invention.

Fig. 4 is a perspective vievv7 of a completed 'blade embodying my invention and constructed in accordance with the method herein described. f 'i ,Fim 5 is a perspective vienT of several comp eted blades assembled in a row.

Fig. 6 is a fragmental sectional view of the rotor element of a turbine or similar apparatus equipped with blades embodying my invention.

The method herein described as an embodiment of my invention consists in forming a shroud member and a shroud engaging tip on the outer end of a forged, drawn or cast blade, and then bending the shrouding member so formedto an operative position,

or at right angles to the longitudinal axis.

of the blade.

In carrying out this method I first shear the Wings of the blade at a point intermediate the ends of the blade and at a distance from the free end equal to the desired length of the shroud member. I then press the partially severed portion of the blade sn that the Wing portions thereof are flattened out, as is shown in full lines in Fig. l. It will be understood by those skilled in the art that the shearing and pressing of the WingsA may be done simultaneously, or in one operation. After the partially severed portion of the blade has been pressed so that its Hattened face defines a plane tangent to the concave face of the blade and normal to the longitudinally extending axial plane which bisects the blade, the severed portion is milled to form a flat longitudinally extending Wing 9 and a longitudinally extendingtip 10.v The milling operation is preferably so performed that the flat face of the partially severed portion of the blade, shown in Fig. 1, remains intact and forms one face of the completed wing.

The Wing 9 is then bent about its point of union with the blade proper, and may be simultaneously sheared to the desired shape and punched as at 11 to receive a shroud engaging tip 10 of the adjacent blade. The Wing so bent and she-ered forms a. shrouding member 9a for the outer end of the blades, since it engages the severed ends of the blade Wings and overhangs the concave face of the blade. In assembling the blades, the shroud member of one blade is engaged by the shroud engaging-tip of the next adjacent ing member of the next adjacent blade to forni a continuous shroud. TVith this arrangement blades mounted iu an annular row will be provided with a substantially continuous annular shroud.

The shrouding members of the blades illustrated are provided with a recess 12 at one edge and a tongue or projection 1.5 at the other edge, which is adapted to engage the recess 12 of the next adjacent shrouding member when the blades are assembled. `With this arrangement the shrouding members coperate, independently of the shroud engaging tips 10, to hold the ends of the blades against lateral as well as circumferential vibrations. sembled, the shroud member of each blade is positively locked to the next adjacent blade by riveting over, crimping or distorting the shrouding member engaging tips 10.

In Fig. 6, I have illustrated blades having inclinedshroud members for the purpose of providing Huid passages through the blades of gradually increasing area. This is acblade and also coperates with the shroud- After the blades are ascomplished by severing the blade Wings at an angle instead of at right angles as shown in Fig. l, and then proceeding as already described.

While I have illustrated one embodiment of the method forming a part of my present invention, it Will be apparent that the method may be varied materially Without departing from the spirit and scope of' the invention and that the blades made in accordance With my improved Lmethod may also be varied in details of construction Without departingfrom the spirit and scope of the invention as set forth by the appended claims. f

What I claim is:

l. A methodv of. forming a shrouded blade, which consists in forming a shroud member on the end of a blade, and then bending the member so formed at an angle to the aXis of the blade.

2. A method of forminga shrouded blade, which consists' in milling :a longitudinally extending shroud member on a blade, then bending the member so formed at an angletothe longitudinal -aX'is of the blade.

3. A m-ethod of constructing a shrouded blade, Which consists in partially4 severing the outer end of a blade, flattening one face of the severed portion, then milling a shroud member from the flattened portion, and then bending the member so formed to an operative position With relation to the blade.

4. A method of constructing a shrouded blade, Which consists in partially severing the outer endof a blade, pressing the Wings of the severed portion into substantially the same plane, then milling the partially severed portion to form a longitudinally eX- terrding shrouding member and bending the member at an angle to the longitudinal axis of the blade. f

5. A method of constructing a shrouded blade, which Consists in partiallyl severing the outer end of a blade, pressing Ithe Wings of the severed portion into substantially the same plane, then milling the partially severed portion to -form a longitudinally eX- tending shrouding member, and a shroud engaging tip on the blade, and bending the member at an angle to the ,longitudinal axis of the blade.

y6. A method of constructing a shrouded blade, which consists in partially severing the outer end of a blade, pressing the Wings of the severed portion into substantially the same plane, then milling the partially severed portion to form a longitudinally extending shrouding member, and a shroud engaging tip on the blade, bending the member at an angle to the longitudinal axis of the blade, and punching said member to form a tip-receiving aperture therein.

7. A method of constructing a shrouded blade, Which consists in partially severing the outer end of a blade, pressing the wings of the severed portion into substantially the salne plane, forming a shroud member from the partially severed portion, and then pressing the member so formed into engagement With the severed ends of the undistorted Wings of' the blade.

8. The method of constructing a blade which consists in flattening one face of the outer end of the blade, milling a shroud member from the flattened portion and bending the vshroud member to an operative position.

9. The method of constructing a blade which consists in flattening one face of the outer end of the blade and then forming a shroud member from the flattened portion.

l0. The method of forming a shrouding for the end of a blade, which consists in par- `tially severing a portion at the outer end of the blade, flattening one face of the partially severed portion, and then bending the partially severed portion at an angle to the axis of the blade.

In testimony whereof, I have hereunto subscribed my name this 28th day of December, 1914.

- CHRISTIAN GILSON. Witnesses:

C. W. MCGHEE, E. W. MCCAILISTER. 

